In the related art, there is an image forming apparatus that forms an image with toner supplied from a toner cartridge attached to the image forming apparatus itself. The image forming apparatus performs genuine product determining for a toner cartridge attached to the image forming apparatus itself so as to maintain image quality and prevent the image forming apparatus from failing. The genuine product determining determines whether or not the toner cartridge is a genuine product. The image forming apparatus does not form an image if it is determined that the toner cartridge is not the genuine product as a result of the genuine product determining. The image forming apparatus cannot achieve both reduction in an opportunity of image formation performed by the toner cartridge which is not the genuine product and image formation performed by the toner cartridge which is not the genuine product. Accordingly, a user who intends to form an image using the image forming apparatus cannot form an image, and convenience of the user is reduced.